From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 02B221F1520 for ; Fri, 25 Apr 2025 13:10:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745586616; cv=none; b=aSwKDYZ+rPC9KwY+MoucVa2+EuaoBV1lvk0P/Ngl2UKF0H653rpGIPy5UnO+2FR2tgoQLdu4sGHhXMEBH8BfkemvEZVL15S2BWS0jleuOAZRxkKI08i1VPDLHHbFtAgFjWzPP1BYKy3S/8zq/hRO78jaLiA8dVyGa+PNyZYqsSE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745586616; c=relaxed/simple; bh=uda3xHTc7BGkR00UHwzuQGG0SC3PhcWoBxXfneCyEoA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=MXyHAE17UncPxUL1g0hQwMGVw3lMGIZwzgd845DtCu4TIiFJB7IivNyHO6SHxTX4/gZYn+Wam3yFvPvqKd052NwIF26/vb0Fkhl1qVcqVclJou1SKkmsg/slN4VsECYzwaYcXGE2k/NJ0pYgFQ3dUmcUKx1FjEKkB6PG17Ju63c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=ZqfyExAl; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="ZqfyExAl" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=nvgCMNz9z9yzPtz9VMIerNYMuUBGYdLqwKWZIzSPFjU=; b=ZqfyExAl/26bLdo+x/r+dTnM6C Pqxb+iYjkT+MjSKy2oQJH9vHzmwVPXfZIQJnY32HEbc64pPR5jrlYdid6cwI8qbLgWin1ekbCOhZK G5YDrZ7ynPiOrC3BwwkKEmtFHWixU5JYLvQwZV1Ydetmgg+B5PyPnvo0myGrmMYtlZDiSQxtktiLS tmeVWXOBpgJjBkn4seaHIHz9G4pRe/DqikF4gN7wBzxAVOdJtYTwG3Z/EDjS2IHdrd3bcppeVps96 +KA3dioyjLMHiiPRITMUL+BD3sDTZiBO13gHzkD7NL+2alkswws936Yg8LEaW7J0LemVt7Q2Cfa7S ENxExiag==; Received: from hch by bombadil.infradead.org with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1u8Ioo-0000000HEH3-1pFR; Fri, 25 Apr 2025 13:10:14 +0000 Date: Fri, 25 Apr 2025 06:10:14 -0700 From: Christoph Hellwig To: "Darrick J. Wong" Cc: Luca Di Maio , linux-xfs@vger.kernel.org, dimitri.ledkov@chainguard.dev, smoser@chainguard.dev, hch@infradead.org Subject: Re: [PATCH v6 2/4] populate: add ability to populate a filesystem from a directory Message-ID: References: <20250423160319.810025-1-luca.dimaio1@gmail.com> <20250423160319.810025-3-luca.dimaio1@gmail.com> <20250423202358.GI25675@frogsfrogsfrogs> <20250424220041.GK25675@frogsfrogsfrogs> Precedence: bulk X-Mailing-List: linux-xfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250424220041.GK25675@frogsfrogsfrogs> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Thu, Apr 24, 2025 at 03:00:41PM -0700, Darrick J. Wong wrote: > The thing is, if you were relying on atime/mtime for detection of "file > data changed since last read" then /not/ copying atime into the > filesystem breaks that property in the image. I don't think that matter for images, because no software will keep running over the upgrade of the image. Also plenty of people run with noatime, and btrfs even defaulted to it for a while (not sure if it still does). At the same time having the same behavior as mkfs.ext4 is a good thing by itself because people obviously have been using it and consistency is always a good thing. > How about copying [acm]time from the source file by default, but then > add a new -p noatime option to skip the atime? I'd probably invert the polarity. When building an image keeping atime especially and also ctime is usually not very useful. But that would give folks who need it for some reason a way to do so.